As many as 25 swine flu cases have been detected in West Bengal this year so far, an official said on Friday.

"From January 1 till today (April 21), we have recorded 25 cases. This is the normal pattern and there is no reason to panic," said state' Director, Health Services, B.R. Satpathy. The flu is caused by the H1N1 virus. In 2015, India had witnessed a major outbreak of the disease with Gujarat and Rajasthan being the worst-affected. This year, the virus has claimed around 123 lives in Maharashtra.